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प्रश्न
A voltmeter has a resistance of 100 Ω. What will be its reading when it is connected across a cell of emf 6 V and internal resistance 20 Ω?
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उत्तर
Terminal potential, V = `"E"/("R" + "r") xx "R" = 6/(100 + 20) xx 100 = 5`V
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